docs: def get_touch_dict(self, ind=None, out=bool):
          """ Get a dictionnary of Cls_Name struct with indices of Rays touching
  
          Only includes Struct object with compute = True
              (as returned by self.lStruct__computeInOut_computeInOut)
          Also return the associated colors
          If in is not None, the indices for each Struct are split between:
              - indok : rays touching Struct and in ind
              - indout: rays touching Struct but not in ind
  
          """
          if self.config is None:
              msg = "Config must be set in order to get touch dict !"
              raise Exception(msg)
  
          dElt = {}
          ind = self._check_indch(ind, out=bool)
          for ss in self.lStruct_computeInOut:
              kn = "%s_%s"%(ss.__class__.__name__, ss.Id.Name)
              indtouch = self.select(touch=kn, out=bool)
              if np.any(indtouch):
                  indok  = indtouch & ind
                  indout = indtouch & ~ind
                  if np.any(indok) or np.any(indout):
                      if out == int:
                          indok  = indok.nonzero()[0]
                          indout = indout.nonzero()[0]
                      dElt[kn] = {'indok':indok, 'indout':indout,
                                  'col':ss.get_color()}
          return dElt